Significance 192 IgG saporin is an antibody to low affinity NGF receptors (NGFr) coupled to a cytotoxin. When given to rats via the cerebral ventricles it selectively kills cholinergic cells. These are the same cell populations effected in Alzheimer's Disease. Objectives This pilot project is to determine if 192 IgG saporin has the same effect in rhesus macaques. If so this could present an induced animal model for Alzheimer like disorders. Two pilot groups of animals will be tested. Each group will consist of two animals. The first group will have IgG saporin administered in the ventricles and the second group will have injections to the basal forebrain. Results Initial results show that the current formulation of cytotoxin may have poor affinity for NGF recptors. The current batch of 192 IgG saporin is being evaluated in cell culture to determine problems in antibody specificity. Future Directions Once a lot of saporintoxin is obtained with appropriate sensitivity and specificity further labeling studies will be performed.